Communicating With The Cellular Modem

Interfacing with the cellular modem is only available via CLI.

Usage  
mmcli [OPTION?] Control and monitor the ModemManager.
Option Description
-h, --help Show help options
--help-all Show all help options
--help-manager Show manager options
--help-common Show common options
--help-modem Show modem options
--help-3gpp Show 3GPP related options
--help-cdma Show CDMA related options
--help-simple Show Simple options
--help-location Show Location options
--help-messaging Show Messaging options
--help-voice Show Voice options
--help-time Show Time options
--help-firmware Show Firmware options
--help-signal Show Signal options
--help-oma Show OMA options
--help-sim Show SIM options
--help-bearer Show bearer options
--help-sms Show SMS options
--help-call Show call options
Application Options Description
-v, --verbose Run action with verbose logs
-V, --version Print version
-a, --async Use asynchronous methods
--timeout=[SECONDS] Timeout for the operation

5G Settings and behavior

Standalone versus non-standalone operation

The 10G-5G modules can connect in either standalone (SA) or non-standalone (NSA) mode.

5G-NSA employs a simultaneous 5GNR and LTE core connection. Data transfer occurs over 5G, while control aspects of the network use 4G technology. Depending on the carrier, the 5G connection may go dormant when inactive, activating either when data transfer begins or after a certain data transfer threshold.

To show which network the module is connected to, use the AT!COPS? command, which returns the following:

+COPS: [selection mode],[operator format],[operator],[access technology]

Example:

root@cm8196-10g-5g-tp2-p29:~# mmcli -m a --command='AT+COPS?'
response: '+COPS: 0,0,"Telstra",13'

This example shows access technology 13 (5G-NSA), which corresponds to the following table.

2 (UTRAN) 3G
7 (E-UTRAN) 4G

11 (NR connected to a 5GCN)

5G SA
13 (E-UTRA-NR dual connectivity) 5G NSA
Determining 5G status

Determining the 5G status requires two commands:

  • AT+COPS? : First, use this command to see if there is a 5G-NSA connection (see above).

  • AT!GSTATUS? : Then, run this command and check if system_mode is LTE (to indicate that 5G is dormant) or ENDC (to indicate that 5G is active).

Forcing a 5G or LTE connection

To force a 5G or LTE connection, use the “nas-set-system-selection-preference” and “AT!RATCONFIG” commands:

Action Command Example
Force 5G-SA qmicli -p -d /dev/wwan0qmi0 --nas-set-system-selection-preference="5gnr",automatic
Disable 5G-NSA AT!RATCONFIG="NR",2

qmicli -p -d /dev/wwan0qmi0 --nas-set-system-selection-preference="lte|5gnr",automatic
Force 5G-NSA AT!RATCONFIG="NR",1

qmicli -p -d /dev/wwan0qmi0 --nas-set-system-selection-preference="lte|5gnr",automatic
Force LTE qmicli -p -d /dev/wwan0qmi0 --nas-set-system-selection-preference="lte",automatic